[pgpool-committers: 8992] pgpool: Doc: Bump doc version to 4.0.21

[Bo Peng]

Doc: Bump doc version to 4.0.21

Branch
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V4_0_STABLE

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=5a5d9ec80caa6b7611e466a3f383b2f7f3227e71

Modified Files
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doc.ja/src/sgml/version.sgml | 2 +-
doc/src/sgml/version.sgml    | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)